In all patients the percentage of activated lymphocytes with surface expression of IL12Rb1 was <1% indicating that it is an effective method for the screening of these patients. Three recurrent mutations were responsible for 85% of our families. Prognosis was good in patients, in whom specific antimicrobial therapy was given before dissemination occurs, as well as prophylactic antimicrobial treatment when needed and IFN-γ therapy for severe infectious episodes.

Streptococcus pneumoniae is a common pathogen responsible for pulmonary infections and the leading cause of mortality and morbidity in patients with particularly B cell immunodeficiencies. Antibody production is the principal protective immune response against S. pneumoniae and measurement of the production of antipolysaccharide antibodies is important in the evaluation of B cell deficiencies. We quantified serotype-specific immunoglobulin G antibodies against seven common pneumococcal serotypes before and three weeks after unconjugated vaccine in 416 patients with recurrent respiratory tract infections; fifty-five (13%) of whom showed impaired antibody response. We could evaluate 41 of these 55 patients for their particular clinical features. Specific antibody deficiency, was diagnosed in 10 of these patients, common variable immunodeficiency in 18, ataxia telangiectasia in 10 and other antibody deficiencies in 7 (transient hypogammaglobulinemia in 4, IgG subclass deficiency in 1, partial and selective IgA deficiency in 1) patients. Evaluation of the antibody response to polysaccharide antigens should be considered early on in patients with recurrent respiratory infections and required particularly for the diagnosis of specific antibody deficiency and the decision of the appropriate treatment approaches.

In recent years subcutaneous immunoglobulin is widely used for primary immunodeficient patients. Subcutaneous administration provides a more stable and higher serum immunoglobulin levels due to continuous and steady transition from lymphatics to the systemic circulation. We aimed to evaluate the changes in serum immunoglobulin levels under subcutaneous immunoglobulin therapy in patients with primary immunodeficiency with or without secondary protein loss. Nine patients with primary immunodeficiency who switched to subcutaneous immunoglobulin were enrolled. Age, gender, diagnosis, reasons of transition to subcutaneous route, reasons of secondary protein loss were recorded. A questionnaire consisting of frequencies and types of infections, side effects observed with intravenous and subcutaneous routes; date and reason of transition to subcutaneous route were asked to all participants. Serum immunoglobulin levels at the 3rd and the 6th months before and after subcutaneous route were recorded. Of the 9 patients (M/ F=4/5) the median age was 12 years (6.1-28.7) and 5 of them had protein loss. In total, 444 injections were applied, and all patients experienced local reactions. Infections were more frequent under intravenous than subcutaneous route (p=0.004). We observed an increase in immunoglobulin levels under subcutaneous route (p=0.069 at 3rd; p=0.13 at 6th month). This increase was evident at the 3rd month of transition to subcutaneous route in patients with protein loss (p=0.080). There was an increase in serum immunoglobulin levels under subcutaneous route. However, increase was not statistically significant since the study group was small. This increment was prominent in patients with protein loss. Subcutaneous administration may be a good alternative for primary immunodeficient patients with protein loss who have persistent low serum immunoglobulin levels despite increments in the intravenous immunoglobulin doses.